Submicron iron powders were produced by reducing ferric chloride(FeCl₃) with hydrogen gas. The dependence of reduction rate on the various parameters were inves-tigated by measuring the conductivity of water through which the reaction gas was passed out. The reduction rate increased with increasing the temperature up to 900℃ and increas-ing both the FeCl₃ partial pressure and H₂: Ar gas ratio up to 3 : 1 The particle size and distribution were affected by all of the above three parameters.